Wish you had a skylight, but don’t have the ability to cut a hole in your roof? MAKE subscriber Chris did to, and wrote in to share his solution to the problem: a pv+led-based ‘fake’ skylight. The concept is pretty simple, but with a nice result. He had some unused capacity on his PV (photovoltatic) solar panel, and basically hooked up a bunch of high power LEDs directly to it. To achieve the ‘skylight’ look, he built a custom metal box with a glass diffuser screen, and mounted the diodes inside of it. He has a nice write-up on his site, along with a calculator to determine how the LEDs should be connected. Excellent work!

Setting up fiberoptic cabling with a diffuser would allow for a skylight that actually fluctuates with the lighting conditions outside. Place a focusing lens outside (or mounted to the corner of a window if you don’t want to drill the hole for the cable), run the cables through the ceiling, and then use the reverse lens plus glass like shown above, and you’ve got a real skylight (with fluctuating lighting effect), without the hole in your roof.

Mr. Fright

I’ve seen something like you describe. It was invented and patented by a professor at some university (I forgot where). Instead of a lens as you suggest, it used a parabolic reflector to concentrate light into a fiber optic cable, and that went inside to a piece of diffusing clear plastic.

He went further to hook up a sensor to the fiber optic cable that controls a dimmer for the electrical light in the room. When there is more sun light coming in, use less electrical light. If its cloudy, the electrical light will be brighter so you always have the same level of light.

To this, I would also suggest when you do not need light in that room, direct the light from the fiber optic cable away from the diffuser with a mirror or something towards a solar panel and store some energy for when there isn’t enough sun.

alandove

My wife and I just installed a fake skylight over our bed, and it definitely helps us get up with fewer cycles of the “snooze” alarm. Our approach was much simpler and cheaper, though: we just picked out a nice-looking fluorescent fixture with an attractive diffuser at Home Depot, wired it to a plug, and attached it to the ceiling with sheetrock anchors.

For bulbs, we ordered full-spectrum T8s from sunbox.com, a company that specializes in light therapy products. The light from these bulbs is very much like sunshine. The fixture is plugged into a digital timer, with different on/off times set for weekdays and weekends. I think the whole project ran about $75 and took a few hours to assemble.

https://me.yahoo.com/paulhildebrandt#05e59

I like his work but from a efficiency standpoint just keeping the light as light as Jonathan suggested would be much better. I’ve seen commercial applications of fiberoptic skylights that are good examples: http://www.huvco.com/products.php?product=parans

jeff-o

It would be neat if a number of smaller, low-power LEDs could be integrated into this skylight, and made to “twinkle” at night.

Elemental LED staff

Yes, setting it up so that the degree of light from the LEDS matched the outdoor conditions is what I was thinking, too! A simulation of the nice fluctuating light of the sky would prevent it from resembling an overhead flurorescent light.

99point99

As mentioned in Chris’ article, the level of light output by the fake skylight matches the level of sunlight outside (the power coming out of the PV fluctuates with the sun, so the light coming out of the LEDs does too).

anon

wheres this guys website they mentioned? im totally interested in doing this myself.